Feed-control valve with contractable tube

Abstract

A feed-control valve for use in a pipe for pneumatically conveying a granular material or transporting a sticky liquid comprises a tubular valve housing, a valve ring having the same inside diameter as that of the tubular valve housing and angularly movably disposed therein, a plurality of flexible, strong and highly stretch resistant and cord spans connected between the valve housing and the valve ring at substantially equally spaced angular positions along their inner surfaces and each span having a length which is substantially the same as the inside diameter of the valve housing or valve ring, and a flexible and strong inner tube mounted in the valve housing and the valve ring and disposed radially inwardly of the plurality of cord spans. The inner tube can be contracted or squeezed radially inwardly by the cord spans from a fully-open position to a fully-closed position in response to angular movement of the valve ring with respect to the valve housing.

What is claimed is: 
     
       1. A feed control valve comprising: a tubular valve housing comprises a tubular wall having an annular guide recess, an inner surface, and an outer surface;   a valve ring angularly movably fitted in said annular guide recess and having an inner surface corresponding to the inner surface of said valve housing;   a plurality of flexible, strong and highly stretch-resistant cord spans connected between said tubular valve housing and said valve ring at substantially equally spaced angular positions along the inner surfaces of said valve housing and said valve ring,   a flexible and strong inner tube having axial ends and mounted in said valve housing and said valve ring and disposed radially inwardly of said plurality of cord spans, said inner tube having annular retainer ribs on said axial ends thereof;   said valve housing having annular grooves in which said annular retainer ribs are fitted;   said valve ring having a handle projecting radially outwardly therefrom for angularly moving said valve ring with respect to said valve housing to enable said cord spans to contract said inner tube radially inwardly from a fully-open position to a fully-closed position;   said valve housing having an arcuate slot through which said handle extends out of said valve housing, whereby said valve ring is angularly movable through an angle defined by said arcuate slot.   
     
     
       2. A feed control valve according to claim 1, wherein said outer surface of said valve housing has notches, said handle of said valve ring is provided with a pawl which selectively engages said notches to retain said handle in the desired angular position with respect to said valve housing. 
     
     
       3. A feed control valve according to claim 2, further comprising flanges that are mounted on the valve housing for connection to external pipes. 
     
     
       4. A feed control valve according to claim 3, wherein each of said cord spans have a length which is substantially the same as the inside diameter of said tubular valve housing. 
     
     
       5. A feed control valve according to claim 3, wherein each of said cord spans have a length which is substantially the same as the inside diameter of the valve ring. 
     
     
       6. A feed control valve according to either claim 4 or 5, wherein said valve ring has the same inside diameter and thickness as said tubular wall of said valve housing. 
     
     
       7. A feed control valve according to claim 6, wherein said tubular valve housing comprises an upper housing member and a lower housing member joined in concentric relation, said lower housing member having said annular guide recess. 
     
     
       8. A feed control valve according to claim 7, wherein said upper housing member and said valve ring have a plurality of pairs of holes, said cord spans comprising a single cord passing successively through said holes and extending parallel to each other. 
     
     
       9. A feed control valve according to claim 6, wherein said valve housing comprises a unitary tubular body having said annular guide recess in which said valve ring is angularly movably fitted, and said arcuate slot communicates with said annular guide recess and through which said valve ring is insertable into said annular guide recess. 
     
     
       10. A feed control valve according to claim 9, wherein said inner tube comprises a flexible and strong outer tube member mounted in said valve housing and said valve ring and disposed radially inwardly of said plurality of said cord spans, and an inner tube member disposed radially inwardly of said outer tube member.